The present invention relates to a physical calendar, comprising a plurality of pages, which have a plurality of calendar areas, each of which identifies a unique time period and is adapted to receive a handwritten entry for that time period. The invention also relates to an arrangement for recording calendar information, a method and a calendar page.
Today, many people use calendars as a memory aid to help them keep track of appointments and various types of tasks that must be carried out at set times, both at home and at work. There are many different types of calendars which can essentially be divided into two main groups: paper-based and electronic.
Paper-based calendars, where the user writes with an ordinary pen in predefined writing areas, are still the most common group. They are usually very reliable and easy to use, but have the drawback that all information written in them is lost if the user should happen to lose the calendar.
In addition to a paper-based calendar, many people use an electronic calendar in their computer at work. Electronic calendars have the advantage that they can usually carry out alarm functions to remind the user about meetings and other activities. However, most people sometimes forget to record the information in their computer as well as in their paper-based calendar.
Fairly recently, several types of portable electronic calendars, so-called PDAs, have come on the market. These are intended to replace the paper-based calendars and have the advantage that they can automatically exchange the calendar information with a computer so that the calendar information the user has in his computer and in his portable calendar is always identical. However, many people still prefer to use paper-based calendars.
It is thus an object of the present invention to obviate the above-mentioned problems of paper-based calendars.
A further object of the invention is to increase the functionality of paper-based calendars.
This object is achieved completely or partly by a calendar according to claim 1, an arrangement for recording calendar information according to claim 13, a method for digital storage of calendar information according to claim 22, and a calendar page according to claim 24. Preferred embodiments are defined in the subclaims.
More specifically, the invention relates to a physical calendar, comprising a plurality of pages, which have a plurality of calendar areas, each of which identifies a unique time period and is adapted to receive a handwritten entry for that time period, each calendar area being provided with an electronically readable code, which is designed for creating an electronic back-up of the handwritten entry made in the calendar area.
In a calendar according to the invention, all entries in the physical calendar can also be recorded electronically without any additional action on the part of the user. This means that the user can have the advantages of both the electronic and the physical calendar.
In this connection, the term xe2x80x9cphysical calendarxe2x80x9d thus refers to a calendar belonging to the paper-based group described in the introduction and having pages made of paper or a similar material which is suitable for receiving handwritten entries made with an ordinary pen.
The calendar areas can be of various shapes, such as boxes or rows of various sizes and can identify different time periods such as months, weeks, days or a specific time on a certain day. In these calendar areas, a user can fill in activities which relate to the respective time period. Each calendar page can have zero, one, or several calendar areas identifying a unique time period.
Each of the above-mentioned calendar areas is thus provided with an electronically readable code, i.e. a code which can be read by means of an electronic aid. The purpose of the code is to enable an electronic back-up of the handwritten entry that the user makes in the calendar area in question. For this purpose, the code may enable the determination of the time period to which the entry relates and/or the digitization of the entry.
It should be noted that a time period should be interpreted broadly. It can be defined by one point in time with respect to its beginning and one point in time with respect to its end, or only a single point in time with respect to both its beginning and its end, or in some other suitable way. As it is used here, the term time period also includes a single point in time.
Preferably the code extends across essentially the entire calendar areas. In this way, the code can be read regardless of where a handwritten entry is made in the areas. The code can advantageously be a position code which indicates a position in the calendar, for example with one or more coordinates. Preferably, the position code codes a plurality of positions in each calendar area. The reason for this is that continuous reading of the position of a pen when a handwritten entry is being made is one way of digitizing the handwritten entry. Furthermore, the position can be translated into a time period. Moreover, the position code is advantageously unique for each calendar area so that a simple reading of the position code will enable the determination of the time period identified by the calendar area. Suitably, the position code can be two-dimensional, so that it codes positions in two dimensions. In this case, it is preferably formed in such a way that one dimension of the position code is unique for each calendar area, making it possible to use this dimension for determining the time period. If the position code is not unique for each time period, some other means must be used for determining the time period. In that case, each of the calendar areas can advantageously also comprise a time code enabling the determination of the time period identified by the calendar area. Alternatively, each of the calendar areas can comprise such a time code only, making it necessary to record the handwritten entry in electronic form in some other way than by using the position code. In this case, one way is to image the handwritten entry electronically or to determine how the pen creating the handwritten entry is being moved, for example with the aid of images or accelerometers. However, it is, of course, advantageous if the same code can be used for both the time determination and the digitization of the entry, not least because this makes it possible for the reading device to use the same sensor for both tasks.
The code can be chemical, magnetic, or of some other type, but preferably it is optically readable, which means that it must be capable of reflecting/absorbing light in such manner that the code can be recorded with a light sensitive sensor. The calendar areas can identify time periods of different length. In this way, all the pages of the calendar need not look the same. For example, one page may correspond to one year, in which case each calendar area may correspond to a month. Another page may correspond to one day, in which case each calendar area corresponds to one hour.
In a preferred embodiment of the calendar, however, the code is a first absolute position-coding pattern which extends across the calendar areas and codes coordinates for absolute positions so that a handwritten entry which is made in a first of said calendar areas can be recorded digitally in the form of a coordinate sequence by detecting the first absolute position-coding pattern and the time period which is identified by the first calendar area can be determined on the basis of the coordinates in the coordinate sequence.
By the absolute position-coding pattern coding absolute positions, all positions which can be detected by means of the absolute position-coding pattern in the calendar areas will be unique. As a result, all the positions within a certain calendar area can be associated with the time period identified by that calendar area, and in this way entries that are made in this calendar area can be related to the associated time period. The absolute position-coding pattern must code positions with such a resolution that handwritten entries can be recorded by means of the pattern with sufficient accuracy.
The absolute position-coding pattern thus has the double function of enabling digital recording of a handwritten entry which is generated as a user moves a pen across the pattern, and defining the unique time period to which the handwritten entry is related.
The first absolute position-coding pattern can advantageously constitute a first subset of a larger absolute position-coding pattern, which first subset codes coordinates for points within a first coordinate area on an imaginary surface, which comprises all points which the larger absolute position-coding pattern is capable of coding, said first coordinate area being dedicated to calendar information.
In this case, the first absolute position-coding pattern thus does not in the first place code absolute positions in the calendar areas, but within an area, dedicated to calendar information, on the imaginary surface. Thus the calendar does not necessarily have coordinates which begin in the origin of coordinates. The advantage of this is that different units, which handle calendar information in the form of coordinates and which besides handle other information recorded by means of other subsets of the absolute position-coding pattern and, thus, also consisting of coordinates, can distinguish the calendar information from the other information and, consequently, distinguish the processing of the different types of information.
The calendar can advantageously have at least one page which is provided with said first absolute position-coding pattern and indications specifying said unique time periods, in which case the first absolute position-coding pattern and said indications are superimposed on each other. The indications can be, for example, alpha-numerical indications which specify the time periods or be limiting markings which distinguish different time periods. Such indications are to be found in normal physical calendars. Here, however, they superimpose or are superimposed by the absolute position-coding pattern. This means that the page contains two information layersxe2x80x94one that can be read with the user""s naked eye and one that can be read electronically. A handwritten entry can constitute a third information layer.
The absolute position-coding pattern absorbs advantageously IR light and can, to this end, be printed with carbon-based black printing ink. If the indications and the handwritten entries are made with the aid of some other type of ink that does not absorb IR, they will not prevent the detection of the absolute position-coding pattern.
In the calendar, advantageously at least one calendar area can be associated with a function field which defines a function or a command that is to be performed with regard to a handwritten entry which is made in this calendar area. When a handwritten entry has been recorded electronically, a user can by means of the function field define how the entry is to be processed. If the entry is recorded electronically with a portable user unit, the user may want to store the entry in his digital calendar in his personal computer. He can then, by using the function field, instruct the user unit that the entry is to be transferred to the personal computer or some other external unit with which the user unit can communicate. As an alternative, recorded entries can be transferred directly to the digital calendar as soon as the user unit gets in contact with the unit containing the digital calendar.
The function field can be provided with a second absolute position-coding pattern. The recording of the command then proceeds in the same way as the recording of the handwritten entry, except that the user unit identifies the coordinates which are coded by the second absolute position-coding pattern as defining the command. Moreover, it is essentially sufficient that the coordinates for one point are detected by means of the second absolute position-coding pattern.
The second absolute position-coding pattern is advantageously a second subset of the larger virtual absolute position-coding pattern, which second subset codes coordinates for points in a second coordinate area on the imaginary surface which is dedicated to the command. In this manner, the same second subset of the absolute position-coding pattern can be used to code the command in a number of positions in the calendar.
Alternatively, each function field relating to one and the same command can be represented by different coordinates and especially by the coordinates for its position in the calendar.
The calendar further advantageously comprises at least one writing area that does not define a time period and that is adapted to receive handwritten entries, said writing area being provided with a third absolute position-coding pattern.
Many physical calendars comprise special pages or areas for address information, non-time-related entries, xe2x80x9cto-doxe2x80x9d lists and the like. Each of these areas can be provided with an absolute position-coding pattern which enables electronic recording of handwritten entries that are made in these areas.
The third absolute position-coding pattern can be a third subset of the larger virtual absolute position-coding pattern, which third subset codes coordinates for points within a third area on the imaginary surface. This area can be, for example, dedicated to address book information or data for a xe2x80x9cto-doxe2x80x9d list or the like so that recorded entries can be identified as intended for storage in, for example, a digital address book or task list.
Also the writing area can be associated with a function field which defines a function or a command that is to be carried out with respect to a handwritten entry that has been made in the writing area. The function field can be designed in the same way as described above.
The command can be, for example, one of storing the handwritten entry, sending a mail containing the handwritten entry, sending an SMS containing the handwritten entry and sending a fax containing the handwritten entry. The writing area can thus be used to send information which is entered in the writing area. This increases the functionality of the paper-based calendar so that it corresponds to that of a modern PDA.
The position code of the calendar is preferably based on a first string of symbols, which contains a first predetermined number of symbols and which has the characteristic that if a second predetermined number of symbols are taken from the first string of symbols, the location of these symbols in the first string of symbols is unambiguously determined, the first string of symbols being used for determining the position in a first dimension on the calendar page; and on a second string of symbols having the same characteristic as the first string of symbols, the second string of symbols being used to determine the position in a second dimension on the calendar page.
Since the position code is based on a string of symbols with a finite number of symbols arranged in a predetermined order, it is possible to define a xe2x80x9cformulaxe2x80x9d for determining the position in a first dimension on the surface. In this way, only a small amount of memory space is required for storing the string of symbols and the position determination can be carried out quickly and easily. The position can, for example, be indicated as a pair of coordinates in a Cartesian or a polar coordinate system.
According to a second aspect of the invention, it relates to an arrangement for electronically storing a handwritten entry which is made in a physical calendar comprising a plurality of pages, which have a plurality of calendar areas, each of which identifies a unique time period and is adapted to receive the handwritten entry, said arrangement being adapted to record the handwritten entry electronically essentially at the same time as it is being made in a first of said calendar areas and to determine the unique time period which identifies the first calendar area, thereby enabling the creation of an electronic back-up of the calendar.
The advantages of this arrangement are evident from that stated above.
According to a third aspect of the invention, it relates to a method for processing calendar information, comprising the steps of electronically recording a handwritten entry that is made in a calendar area in a physical calendar, the recording being made in the form of a coordinate sequence; determining a unique time period to which the calendar area corresponds on the basis of coordinates in said coordinate sequence, and storing the electronically recorded handwritten entry in a digital calendar in connection with a time indication corresponding to the unique time period.
The advantages of this method are evident from that stated above.
According to a fourth aspect of the invention, it relates to a calendar page which is provided with an absolute position-coding pattern which enables electronic recording of a handwritten entry that is made on the calendar page.
The advantages of this aspect of the invention are evident from that stated above. What has been said above regarding the calendar also relates in applicable parts to the calendar page, the method and the arrangement.